Onychomycosis (also known as “dermatophytic onychomycosis,” or “tinea unguium”) is a fungal infection of the nail. It is the most common disease of the nails and constitutes about half of all nail abnormalities. This condition may affect toenails or fingernails, but toenail infections are particularly common. It occurs in about 10% of the adult population.
The most common symptom of a fungal nail infection is the nail becoming thickened and discolored. As the infection progresses the nail can become brittle, with pieces breaking off or coming away from the toe or finger completely. If left untreated, the skin can become inflamed and painful underneath and around the nail. There may also be white or yellow patches on the nail bed or scaly skin next to the nail, and an odor may result. There is usually no pain or other bodily symptoms, unless the disease is severe. People with onychomycosis may experience significant psychosocial problems due to the appearance of the nail, particularly when fingers—which usually are always visible—rather than toenails are affected.
Dermatophytids are fungus-free skin lesions that sometimes form as a result of a fungus infection in another part of the body. This could take the form of a rash or itch in an area of the body that is not infected with the fungus. Dermatophytids can be thought of as an allergic reaction to the fungus.
The causative pathogens of onychomycosis include dermatophytes, Candida, and non-dermatophytic molds. Dermatophytes are the fungi most commonly responsible for onychomycosis in the temperate western countries; while Candida and nondermatophytic molds are more frequently involved in the tropics and subtropics with a hot and humid climate.
Trichophyton rubrum is the most common dermatophyte involved in onychomycosis. Other dermatophytes that may be involved are T. interdigitale, Epidermophyton floccosum, T. violaceum, Microsporum gypseum, T. tonsurans, and T. soudanense. A common outdated name that may still be reported by is Trichophyton mentagrophytes for T. interdigitale. The name T. mentagrophytes is now restricted to the agent of favus skin infection of the mouse; though this fungus may be transmitted from mice and their danders to humans, it generally infects skin and not nails.
Other causative pathogens include Candida and nondermatophytic molds, in particular members of the mold generation Scytalidium (name recently changed to Neoscytalidium), Scopulariopsis, and Aspergillus. Candida mainly causes fingernail onychomycosis in people whose hands are often submerged in water. Scytalidium mainly affects people in the tropics, though it persists if they later move to areas of temperate climate.
All causative pathogens are susceptible to certain toxic gasses, such as ozone, oxides of nitrogen, and similar reactive materials. It is understood that fluid and solid materials may also have similar beneficial anti-pathogenic properties. However, there are a number of problems associated with the use of such anti-pathogenic substances to treat onychomycosis. The nail bed itself can act as a barrier to curative gasses and beneficial anti-pathogenic substances. Thus, there remains a need for a system and method for the treatment of onychomycosis that permits substances to traverse, surround and/or enter the nail bed and similar physiological structures for a beneficial effect.
There also remains an unmet medical need for a topical treatment device and treatment method for onychomycosis that is effective, requiring short treatment times and without the undesirable side effects of the prior art. Many chemical compounds exhibit antifungal (fungistatic or fungicidal) properties, and can be incorporated into creams, lotions, gels, solutions and the like. However, antifungal compounds applied topically (i.e., directly to the nail) do not adequately and consistently penetrate the nail bed to kill the fungus at its source, and thus are not consistently effective.
Thus, an additional or improved apparatus and method for treating onychomycosis is desirable.